Closure



CLOSURE 2 Sheets-Sheet 1 Filed Sept. 27, 1960 INVENTOR. Hare/o L. Norwa y 1, 1963 H. NORWAY 3,090,518

CLOSURE Filed Sept. 27, 1960 2 Sheets-Sheet 2 I +2. I H 4 I I l |||111 y j) J 2 1x I ,4 2 U gg j Q, 46 9 CO far ' 4+ 7 II I H l I I Hg'o/d L. Norway United rates 3,0ii,518 CLOSURE Harold L. Norway, Evanston, Ill., assignor to The Bastian- Blessing Company, Chicago, III., a corporation of Illinois 7 Filed Sept. 27, 1960, Ser. No. 58,711 2 Claims. (Cl. 220-39) This invention relates in general to improvements in closures and more particularly to the formation of a leakproof seal between an integral part of a closure and a sealing member disposed in an open end of a hose fitting mounted in a pressure unit or receptacle.

This invention finds its greatest utility in connection with filler and vapor return valves on which an Acme thread is used for hose connections. The use of an Acme thread for hose connections has been a standard for many years and permits a wide range of different makes of hoses and valves to be readily interchanged. In practice, the hoses are attached to filler and vapor return valves only when the unit or receptacle is being filled. Otherwise, these valves are properly capped so that they will hold any gas or liquid in case of failure of the valve permitting leakage therethrough of the gas or liquid. In providing a suitable closure or cap for these valves, it was found extremely difficult and expensive to form Acme threads in these caps, so that an additional threaded boss in the cap and a corresponding tapped thread in the valve fitting itself were necessary to hold the closure tightly in place. Thus, it is apparent that there was an extreme increase in costs in providing this boss and external threads in the closure or cap as well as the added length for the tapped thread within the valve fittings.

Previous efiforts to eliminate this additional boss and thread for holding the closures in place and to utilize only the Acme threadfor this purpose has been almost entirely unsuccessful. In machining, the large undercut required beyond the Acme thread to clear the way for the tap and to make machining possible makes the closure entirely too large. Attempts to mold the internal Acme thread within these metal closures were impractical because many of the finished units were found to be porous and of an imperfect quality of finish.

It is therefore the primary object of this invention to provide an improved closure which completely eliminates the disadvantages of the prior art and provides a closure having an integral part formed therewith to form a positive leak-proof seal with an open end of a standard Acme thread hose fitting.

It is a specific object of this invention to provide an improved protective closure for forming a sealing relationship with a standard Acme thread hose fitting whereby the closure is secured in place by the Acme threads and is interchangeable with pre-existing closures Another object of this invention is to provide an improved closure having a smooth, contoured seal engaging end of an inner skirt formed integral with the closure.

A further object of this invention is to provide an improved molded closure formed from a nylon material that is substantially free of porosity.

A still further object of this invention is to provide an improved molded nylon closure that has female Acme threads extended substantially to the very bottom of the closure and a closure sealing skirt closely adjacent thereto whereby the sealing effort is carried through the closure body very directly to the Acme threads with minimum body stock requirements.

Another object of this invention is to provide an improved closure molded from nylon which receives the open end of a standard male Acme thread or a fitting establishes a sealing relationship in an opening encircled by the thread and presents a limited pressure area over Patented May 21, W63

its central portion for the force created by the gas being retained to act upon.

A further object of this invention is to provide an improved closure to form a seal with an elastomer sealing member held in a protected position against loss or damage with the confines of a valve fitting and to assure a tight fit at the sealing member with an inward force applied from an external surface of the fitting.

The invention is also characterized by lateral support of the closure skirt against damage to either part by inadvertent lateral blows While there is some resistance remaining in the elastomer sealing member to cushion accidental end blows, the cylindrical flange serving as a reinforcing agent for this purpose whereby the seal is not broken even though the outer skirt may be cracked or chipped. The damage would have to be very extensive before Acme threads would slip and permit release and loss of the protectiveness of the closure since the clearances are in interference clearances unless the closure is unscrewed by rotation.

A still further object of this invention is to provide an improved closure in which the overall amount of body material is substantially reduced, compact in size, efficient and extremely economical to manufacture.

Other and further objects, advantages and features of the present invention will be apparent to one skilled in the art from the following description, taken in conjunction with the following drawings, in which similar reference characters relate to similar parts and in which:

FIG. 1 is a perspective view of the closure of this invention;

FIG. 2 is a bottom plan view of the closure of this invention;

FIG. 3 is a top plan view of the closure of this invention;

FIG. 4 is a sectional view in side elevation of this invention;

FIG. 5 is a sectional View in side elevation illustrating the closure of this invention in sealing relationship with a standard Acme thread hose fitting; and

FIG. 6 is a sectional view in side elevation illustrating a closure of the prior art in sealing relationship with a prior standard Acme thread hose fitting.

In carrying out the objects of the present invention and by way of generalization for a better understanding of the detailed description to follow, the closure hereinafter described is characterized by having an inner skirt integral with the closure which provides a deeper reaching contoured surface for sealin relationship with a rubber sealing member which is disposed within an open end of a standard Acme thread fitting with radial clearance between the inner skirt and the fitting less than the height of the thread from root to crest. The closure is formed from a plastic material such as nylon and provides an outer skirt having Acme threads formed on the inner surface thereof. Concentric With the outer skirtand spaced inwardly therefrom is the inner skirt which provides the contoured sealing end surface to engage the sealing member within the fitting as the internal Acme threads engage the external Acme threads of a standard hose fitting. The outer surface of the skirt portion having the Acme threads formed thereon, provides a plurality of equally spaced vertically positioned ribs or gripping surfaces which have an angular upper surface to insure freedom of rotation of the closure without the ribs engaging a retaining chain that is secured to the hose fitting on the top of the closure. The closure is further characterized by the formation of the Acme threads to the bottom of the closure to insure complete securement thereof with the fitting receiving it and a positive formation of a leak-proof seal before the threads of the fitting bottom on the under surface of the closure.

Referring now to the drawings, the closure of this invention, designated by the numeral 10, is shown in perspective in FIG. 1 and includes an outer skirt 12, an inner skirt 14 and a center boss 16.

Referring specifically to FIGS. 1, 2, 3 and 4, the closure preferably formed from a nylon material, is circular in contour and provides a substantially flat upper surface 13 with the outer skirt 12 depending from the periphery thereof and the center boss 16 and inner skirt 14 concentrically formed with the outer skirt and also depending from the upper surface 18.

The outer skirt 12 provides an external gripping surface 20 having a plurality of equally spaced, vertically positioned ribs 22, integral therewith, with an upper surface 24 of the ribs angularly contoured to provide a smooth surface to prevent the snagging or hooking of a corner of one of the ribs with a retaining chain. An inner surface 26 of the outer skirt 12 has an Acme thread 28 integral therewith which extends from a lower'surface 30 to substantially the bottom of the cap or an under surface 32 of the upper surface 18.

The inner skirt 14 is formed with converging walls 34 extending downwardly from the under surface 32 to form a smooth, rounded, lower sealing surface 36. Readily viewed in FIG. 4, the sealing surface 36 is substantially recessed in elevation to that of surface 30 of the outer skirt 12. It is also readily viewed in FIG. 2 and FIG. 4 that the inner skirt 14 in addition to having'a lower surface at a substantially shorter length than that of the outer skirt, is also concentrically formed at a spaced interval inwardly from the outer skirt. The advantages derived from this specific dimensional relationship as just explained, will be readily apparent as the description continues. v

The center boss 16, formed in the center of the under surface 32, provides material for forming an opening 38 from the upper surface 18 to a depth substantially past half of the thickness of the post 16 to provide a means for pivotally securing a retaining chain indicated by numeral 40, as shown in FIG. 5. This pivotal securing of the chain 40 permits rotation of the closure without interference from the chain, but still permits retaining of the closure to the hose fitting whereby it will not be misplaced, damaged or permitted to be contaminated with foreign particles by contact with a floor surface or other areas providing abrasive particles.

Referring now to FIG. 5, the closure 10 is illustrated in a sealing position on a standard Acme thread hose fitting 42 which provides an externally threaded lower portion 44 for securing the fitting into a valve, tank or unit 'to be filled. A sealing member 46, disposed in the upper portion of the fitting, is deformed to a sealing position by force exerted thereon as the contoured surface 36 of the closure engages an upper surface thereof when the closure is rotated to the closed or tightened position on the fitting. The spacing of the inner skirt 14 relative to the outer skirt 12 being such as to permit the inner skirt to telescope within the inside of the fitting with the surface 36 aligned for engagement with the sealing member 46 before the Acme threads of the fitting bottom on the surface 32 of the closure. The fitting 42 has a wrenching surface 48 formed on its lower inner surface to assist in mounting the fitting into the valve and also as a safety measure to prevent removal except when required and by trained personnel; 7

Referring now to FIG. 6, a closure 10 and hose fitting 42' of the prior art is illustrated andprovides a similar lower external thread 44 for mounting the fitting into a valve. A wrenching surface 48' is provided on the external surface of the fitting since the internal surface is threaded for receipt of a holding threaded portion 50 of the closure 10' which does not provide an internal Acme thread for engagement with the fitting.

A comparison of FIG. 5, showing the closures of this invention, with FIG. 6 showing a closure used for many years, readily illustrates the many structural advantages of this invention. The dimensions marked A and A show the same pressure areas which the closures considered present, and the fact that the invention is able to retain such pressure with a greatly reduced amount and a minimum of material and weight. The dimension C and C further illustrates the compactness of the closure of this invention and a further saving of material and weight, and the elimination of the extensive threads and the large downward extending boss of the conventional closure. Moreover, even though the closure of this invention will function equally as well on the old style fittings, its unique features and structural design permits a much more comp-act fitting (reference to dimension BB') to be formed with the wrenching portion located inside the fitting rather than outside which results in a much flatter overall unit and consequently a substantial saving in the overall length of the valve.

A unique feature of the closure of this invention is that the spaced relationship of the inner skirt sealing surface with the Acme clamping or holding threads of the outer skirt permits such an increase in pressure area that the nylon material has sufiicient flexibility that if there is an increase in internal pressure the upper surface of the cap will load outwardly and create an additional reactive force further tightening the holding of the Acme threads to prevent loosening. The conventional closure, such as shown in FIG. 6, does not provide this flexibility and increased tightening with increase of internal pressure. It being understood of course, that any flexing of the upper surface of the closure of this invention is readily determined by the contour and thickness of the nylon at this surface.

The closure has been illustrated as molded from a nylon material which readily permits the forming of the Acme threads to the very bottom of the closure and the unit requires little if any machining after the molding operation and the porosity of this nylon material is considered to be negligible. In practice, it is found that in differently colored closures formed from the nylon material may be used to distinguish the different liquids on gases within the units.

A further advantage is provided with the structure and lightness of the closure in that the fitting 42 is very often subjected to vibrations that loosen the conventional closure as where the fitting is mounted upon a truck supply service tank or the fitting is used with a fuel supply tank on a motor vehicle. Not only does the lightness of the nylon material greatly reduce the hazard of the closure shaking loose but also the resiliency of nylon between the seal engagement and the Acme threads established by the heavy closure force that is withstood by the Acme threads prevents any vibration being set up at the seal engagement. Also the large diameter of the Acme threads reduces pendulation of a mass such as the heavy mass of the conventional closure about their finer threads of reduced diameter spaced downwardly therefrom.

While only one embodiment of this invention has been shown and described, it is to be understood that various modifications thereof may be apparent to those skilled in the art without departing from the spirit and scope of this invention and, therefore, the same is only to be limited by the scope of the prior art and the appended claims.

What is claimed is: v v

1. In combination with an externally coarse threaded conduit fitting end portion having an internal shoulder spaced from the open end thereof and facing outwardly, an annular resilient sealing member resting on the shoulder with the outer surface thereof spaced a predetermined distance from the open end of said fitting portion, an integral closure of resilient plastic material having a re silient top wall, an outer skirt depending marginally from the top wall having a coarse thread on the inner surface thereof extending substantially the full length of the outer wall for mating engagement with said external coarse thread, external hand grip reinforcing rib members extending radially outwardly from the outer surface of said outer skirt and extending longitudinally of said skirt a distance less than the length of the skirt and terminating in radially reduced ends adjacent to the upper face of said top wall, an inner skirt depending from the top wall a distance greater than said predetermined distance in concentric spaced relationship with respect to said outer skirt to receive the fitting end portion telescopically between said skirts, said inner skirt having its greatest outside dimension substantially smaller than the inside dimension of said fitting end portion to dispose the sealing surface in free alignment with the resilient sealing element, said inner skirt terminating in an axially directed contoured sealing surface for rotational and compressive engagement with the sealing member within said hose fitting at an elevation Within the lower extremity of said outer skirt to provide a positive leak-proof seal therewith prior to the closure reaching its maximum downward threaded position, said top wall between said skirts resiliently transmitting axial pressure exerted against said sealing member to said outer skirt and said coarse thread engagement.

2. In combination with an externally coarse threaded conduit fitting end portion having an internal shoulder spaced from the open end thereof and facing outwardly, an annular resilient sealing member resting on the shoulder with the outer surface thereof spaced a predetermined distance from the open end of said fitting portion, a closure comprising an integrally formed plastic body of semi-rigid resilient material having a top wall, an internally threaded outer skirt depending from the periphery of the top wall having a heavy thread on the inner surface thereof extending substantially the full depth thereof engageable with the heavy thread on the fitting portion and external hand grip rib members extending longitudinally along the outer surface of the outer skirt over the length of said thread reinforcing said outer skirt, said ribs extending longitudinally over said skirt a distance less than the length of the skirt and terminating in radially tapered ends adjacent to said top wall, an inner skirt formed by converging walls depending from the top wall concentric to and spaced inwardly from said outer skirt and telescoping freely into said fitting portion through said open end in alignment with said sealing member, said inner skirt extending a major portion of the length of the outer skirt but from said top wall distance greater than said predetermined distance to provide clearance at all times between said top wall and the upper end of said conduit fitting portion and terminating in an axially directed rounded sealing surface to engage said sealing member in sealed relationship under torque induced compression, said top wall between said skirts resiliently transmitting the axial pressure between said shoulder and said fitting portion that is exerted through said resilient sealing member, said skirts and a tightened threaded engagement between the heavy threads on the outer skirt and on said fitting portion.

References Cited in the file of this patent UNITED STATES PATENTS 727,470 Smelker May 5, 1903 848,785 Towle Apr. 2, 1907 1,634,284 Dunzweiler et a1 July 5, 1927 2,026,889 Gray et a1. Jan. 7, 1936 2,339,702 Isele Ian. 18, 1944 2,440,149 McGinnis Apr. 20, 1948 2,582,721 Roshkind Jan. 15, 1952 2,801,022 Evenblij July 30, 1957 2,950,033 Henchert Aug. 23, 1960 FOREIGN PATENTS 344,904 Germany Dec. 2, 1921 12,162 Netherlands Mar. 16, 1925 209,870 Australia Aug. 21, 1957 809,709 Great Britain Mar. 4, 1959 

2. IN COMBINATION WITH AN EXTERNALLY COARSE THREADED CONDUIT FITTING END PORTION HAVING AN INTERNAL SHOULDER SPACED FROM THE OPEN END THEREOF AND FACING OUTWARDLY, AN ANNULAR RESILIENT SEALING MEMBER RESTING ON THE SHOULDER WITH THE OUTER SURFACE THEREOF SPACED A PREDETERMINED DISTANCE FROM THE OPEN END OF SAID FITTING PORTION, A CLOSURE COMPRISING AN INTEGRALLY FORMED PLASTIC BODY OF SEMI-RIGID RESILIENT MATERIAL HAVING A TOP WALL, AN INTERNALLY THREADED OUTER SKIRT DEPENDING FROM THE PERIPHERY OF THE TOP WALL HAVING A HEAVY THREAD ON THE INNER SURFACE THEREOF EXTENDING SUBSTANTIALLY THE FULL DEPTH THEREOF ENGAGEABLE WITH THE HEAVY THREAD ON THE FITTING PORTION AND EXTERNAL HAND GRIP RIB MEMBERS EXTENDING LONGITUDINALLY ALONG THE OUTER SURFACE OF THE OUTER SKIRT OVER THE LENGTH OF SAID THREAD REINFORCING SAID OUTER SKIRT, SAID RIBS EXTENDING LONGITUDINALLY OVER SAID SKIRT A DISTANCE LESS THAN THE LENGTH OF THE SKIRT AND TERMINATING IN RADIALLY TAPERED ENDS ADJACENT TO SAID TOP WALL, AN INNER SKIRT FORMED BY CONVERGING WALLS DEPENDING FROM THE TOP WALL CONCENTRIC TO AND SPACED INWARDLY FROM SAID OUTER SKIRT AND TELESCOPING FREELY INTO SAID FITTING PORTION THROUGH SAID OPEN END IN ALIGNMENT WITH SAID SEALING MEMBER, SAID INNER SKIRT EXTENDING A MAJOR PORTION OF THE LENGTH OF THE OUTER SKIRT BUT FROM SAID TOP WALL DISTANCE GREATER THAN SAID PREDETERMINED DISTANCE TO PROVIDE CLEARANCE AT ALL TIMES BETWEEN SAID TOP WALL AND THE UPPER END OF SAID CONDUIT FITTING PORTION AND TERMINATING IN AN AXIALLY DIRECTED ROUNDED SEALING SURFACE TO ENGAGE SAID SEALING MEMBER IN SEALED RELATIONSHIP UNDER TORQUE INDUCED COMPRESSION, SAID TOP WALL BETWEEN SAID SKIRTS RESILIENTLY TRANSMITTING THE AXIAL PRESSURE BETWEEN SAID SHOULDER AND SAID FITTING PORTION THAT IS EXERTED THROUGH SAID RESILIENT SEALING MEMBER, SAID SKIRTS AND A TIGHTENED THREADED ENGAGEMENT BETWEEN THE HEAVY THREADS ON THE OUTER SKIRT AND ON SAID FITTING PORTION. 